1. Field of the Invention
The present invention relates to an apparatus for preventing a vibration of an image of an optical system caused by a vibration and, more particularly, to an anti-vibration optical device suitable for a camera, a video camera, a telescope, and the like.
2. Related Background Art
In recent years, as disclosed in U.S. Pat. No. 5,270,857, in a zoom lens system in which a given lens group in the zoom lens system is shifted in a direction perpendicular to the optical axis to perform an anti-vibration operation, an anti-vibration optical system for, when a vibration occurs, controlling the compensation amount for compensating for the vibration in accordance with a zooming state of the zoom lens system is proposed.
However, when the lens group (to be referred to as an anti-vibration lens group hereinafter) to be shifted in an anti-vibration operation for compensating for a vibration is not arranged at the most object side, an ideal shift amount of the anti-vibration lens group for an identical vibration angle varies between an infinity focusing state and a near-distance focusing state. For this reason, when an anti-vibration operation in the near-distance focusing state is performed by a vibration compensation amount proposed in U.S. Pat. No. 5,270,857, a sufficient anti-vibration effect cannot often be obtained.